Field of the Invention
The invention relates to a conveyor belt system comprising a frame with a conveyor belt which is provided so as to be driven by at least two rollers so that the upper belt functions as transport surface and the lower belt functions as return.
Conveyor belts are much used to move materials between a first location and a second location. The invention relates particularly here to conveyor belts which are adapted to transport bulk materials, also known as bulk cargo or bulk goods. These are materials which are not packed individually and loaded and transported, such as containers, pallets or boxes, but which are deposited in bulk in a loading space, processed and transported. The invention is more particularly optimized for the transport of bulk materials with fine particles. Examples hereof are sand, powder, glass dust. Where the word ‘materials’ is used in the remainder of the description, this is understood to mean bulk materials as described above. The materials comprise multiple particles, grains or particulate.
For the transport of materials a conveyor belt is provided with upper standing walls with a mutual spacing which at least at the position of the upper belt is smaller than the width of the conveyor belt. The materials are held in place between the upper standing walls and are supported by the upper belt, which then functions as transport surface for transporting the materials from the infeed of the conveyor belt to the outfeed of the conveyor belt. An operating zone is hereby defined on the conveyor belt between the standing walls. It is impossible, particularly when the materials comprise small particles, to hold all particles between the upper standing walls. The particles which come to lie outside the operating zone, for instance by moving under the upper standing walls, form contaminants which can adversely affect the operation of the conveyor belt.
Description of the Related Art
In most conventional conveyor belt systems it is not possible to prevent such contaminants fouling the interior of the conveyor belt system. A typical problem occurs when the contaminants come to lie on the lower belt functioning as return. These contaminants then come to lie on an inner side of the conveyor belt where they foul the two rollers and other drive and guide elements in the conveyor belt. This will ultimately cause increased wear or even blockage of the conveyor belt system. Much attention is therefore focused in conventional conveyor belt systems on the seal between the upper standing walls and the conveyor belt. This sealing is optimized in order to minimize leakage and the adverse consequences thereof.
EP 2 944 587 describes a conveyor belt system which provides an improved solution to the above described problem. A standard conveyor belt system has a frame and the conveyor belt protrudes on either side through the walls of the frame so that the sides of the conveyor belt are situated outside the frame. Because the conveyor belt lies with its edges outside the frame, contaminants falling via the side of the conveyor belt will not come to lie inside the frame. The structure of the construction prevents with certainty the possibility of contaminants coming into contact with drive elements located in the frame of the conveyor belt system. This considerably reduces the chance of wear and/or blockage of the conveyor belt.